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991.
Salvadora oleoides Decne. is a pharmaceutically important plant. Owing to poor seed formation, viability and, germination, and to anthropogenic disturbances, this species is on the verge of extinction. A reproducible micropropagation protocol to increase the population through tissue culture has been standardized and the results are reported here. Callus tissues were initiated from young leaves and stem explants. Leaf calluses proliferated with 1.5 mg/L BAP and 0.9 mg/L 2, 4-D with additives and continuous slow proliferation up to 15 weeks on 0.5 mg/L BAP and additives with 200 mg/L activated charcoal.Direct shoot initiation took place from stem node explants after 12 days; 4–5 shoots per node were produced in 30 days. Shoot clumps elongated and grew further on MS media supplemented with 2 mg/L BAP, 0.2 mg/L NAA and additives, which generated 20–23 shoots. The elongated shoots induced tap roots with 4 mg/L NAA and200 mg/L activated charcoal in 12 days. In vitro raised plants produced secondary roots when transferred to pots containing vermiculite maintained at 28–35 ℃. The plantlets successfully acclimatised in pots containing soil in natural conditions.  相似文献   
992.
This paper exploits the information obtained in Annual Survey of Industries during 1999–2010 to gauge the degree of value-added owing to the use of traditional inputs (capital, labor, energy, indigenous materials, and imported materials) and advanced industrial production technology (services, information and communications technology, and pollution control equipment) in two main sub-sectors of the Pulp and Paper (P&P) industry in India categorized according to use of different types of raw material. The panel data econometric exercise confirms that the use of traditional inputs and advanced industrial technologies, and industry level determinants of the two sub-sectors have varied effects on value-added within them. These findings are important for promoting higher value-added production in different sectors within the resource-based industry.  相似文献   
993.
994.
Understanding the economic effects of regulations on US aquaculture farms provides insights into which compliance costs create the greatest compliance burden on farms. This can further guide strategies to improve the efficiency of regulatory frameworks and potentially reduce on-farm compliance costs while maintaining adequate oversight. This study estimated the regulatory compliance burden on US catfish farms as part of a national effort to quantify the cost of regulations on US aquaculture farms. Completed survey interviews of catfish farms in the major catfish-producing states covered 63% of the total US catfish production area. Total regulatory costs of the US catfish industry were estimated at $45 million annually. Lost farm revenues (measured as the value of lost production, the value of markets lost from regulations, and the value of business opportunities lost because of regulations) were estimated to be $35 million per annum. Catfish-producing states outside the Alabama/Arkansas/Mississippi region had the highest ($2856/ha) and Alabama the lowest ($1127/ha) regulatory costs per hectare among the surveyed states. The greatest regulatory cost burden on catfish farms ($18 million) was caused by environmental regulations related mostly to the management of federally protected piscivorous migratory birds, followed by labor regulations ($12 million), and taxes/insurance ($7 million). Regulatory costs ($/kg) were 2.6 times higher on smaller (<80 ha) farms relative to larger (>300 ha) farms. Attention is needed to identify alternative regulatory frameworks that provide the same degree of regulatory oversight but are more cost-efficient.  相似文献   
995.
A 60-day feeding trial was conducted to study the effect of exogenous enzymes (xylanase and phytase) supplementation in the non-fermented and fermented de-oiled rice bran (DORB)-based diet of Labeo rohita. Four test diets (T1-DORB-based diet, T2-fermented DORB-based diet, T3-phytase and xylanase supplemented DORB-based diet, and T4-phytase and xylanase supplemented fermented DORB-based diet) were formulated and fed to the respective groups. Test diets T3 and T4 were supplemented with 0.01% xylanase (16,000 U kg?1) and 0.01% phytase (500 U kg?1) enzymes. One hundred twenty juveniles of L. rohita, with an average weight 5.01?±?0.02 g, were stocked in 12 uniform size plastic rectangular tanks in triplicate with 10 fishes per tank following a completely randomized design (CRD). Exogenous enzyme supplementation to the T3 group significantly improved the growth performance of L. rohita (p?<?0.05). Fermented DORB fed groups registered significantly lower growth irrespective of the supplementation of exogenous enzymes. The carcass composition (except CP %), enzyme activities (except amylase activity), globulin, and A/G ratio did not vary significantly (p?>?0.05). Based on the results of the present study, it is concluded that exogenous enzyme supplementation significantly increases the growth of fish fed with DORB-based diet.  相似文献   
996.
Malted cereals are rich sources of alpha-amylase, which catalyzes the random hydrolysis of internal alpha-(1-4)-glycosidic bonds of starch, leading to liquefaction. Amylases play a role in the predigestion of starch, leading to a reduction in the water absorption capacity of the cereal. Among the three cereal amylases (barley, ragi, and jowar), jowar amylase is found to be the most thermostable. The major amylase from malted jowar, a 47 kDa alpha-amylase, purified to homogeneity, is rich in beta structure ( approximately 60%) like other cereal amylases. T(m), the midpoint of thermal inactivation, is found to be 69.6 +/- 0.3 degrees C. Thermal inactivation is found to follow first-order kinetics at pH 4.8, the pH optimum of the enzyme. Activation energy, E(a), is found to be 45.3 +/- 0.2 kcal mol(-)(1). The activation enthalpy (DeltaH), entropy (DeltaS*), and free energy change (DeltaG) are calculated to be 44.6 +/- 0.2 kcal mol(-)(1), 57.1 +/- 0.3 cal mol(-)(1) K(-)(1), and 25.2 +/- 0.2 kcal mol(-)(1), respectively. The thermal stability of the enzyme in the presence of the commonly used food additives NaCl and sucrose has been studied. T(m) is found to decrease to 66.3 +/- 0.3, 58.1 +/- 0.2, and 48.1 +/- 0.5 degrees C, corresponding to the presence of 0.1, 0.5, and 1 M NaCl, respectively. Sucrose acts as a stabilizer; the T(m) value is found to be 77.3 +/- 0.3 degrees C compared to 69.6 +/- 0.3 degrees C in the control.  相似文献   
997.
998.
This study was attempted to assess the extent of toxicity contributed by Na+ and/or Cl? ions individually, besides their possible additive effects under NaCl using physiological and biochemical parameters. Despite the fact that most annual plants accumulate both Na+ and Cl? under saline conditions and each ion deserves equal considerations, most research has been focused on Na+ toxicity. Consequently, Cl? toxicity mechanisms including its accumulation/exclusion in plants are poorly understood. To address these issues, effects of equimolar (100 mM) concentrations of Na+, Cl? and NaCl (EC ≈ 10 dS m?1) were studied on 15-day-old seedlings of two rice cultivars, Panvel-3 (tolerant) and Sahyadri-3 (sensitive), using in vitro cultures. All three treatments induced substantial reductions in germination rate and plant growth with greater impacts under NaCl than Na+ and Cl? separately. Apparently, salt tolerance of Panvel-3 was due to its ability to exclude Na+ and Cl? from its shoots and maintaining low (<1.0) Na+/K+ ratios. Panvel-3 exhibited better vigour and membrane stability indices coupled with lower reactive oxygen species and lipid peroxidation levels, besides stimulated synthesis of proline, glycine betaine and ascorbic acid. Overall, the magnitude of toxicity was observed in NaCl > Na+ > Cl? manner. Though Cl? was relatively less toxic than its countercation, its effect cannot be totally diminished.  相似文献   
999.
1000.
Tea (Camellia sinensis (L.) O. Kuntze) leaves are a major source of flavonoids that mainly belong to the flavan 3-ols or catechins. Apart from being responsible for tea quality, these compounds have medicinal properties. Flavanone 3-hydroxylase (F3H) is an abundant enzyme in tea leaves that catalyzes the stereospecific hydroxylation of (2S)-naringenin to form (2R,3R)-dihydrokaempferol. We report a full-length cDNA sequence of F3H from tea (CsF3H Accession no. AY641730). CsF3H comprised 1365 bp with an open reading frame of 1107 nt (from 43 to 1149) encoding a polypeptide of 368 amino acids. Expression of CsF3H in an expression vector in Escherichia coli yielded a functional protein with a specific activity of 32 nmol min(-1) mg protein(-1). There was a positive correlation between the concentration of catechins and CsF3H expression in leaves of different developmental stages. CsF3H expression was down-regulated in response to drought, abscisic acid and gibberellic acid treatment, but up-regulated in response to wounding. The concentration of catechins paralleled the expression data. Exposure of tea shoots to 50-100 microM catechins led to down-regulation of CsF3H expression suggesting substrate mediated feedback regulation of the gene. The strong correlation between the concentration of catechins and CsF3H expression indicates a critical role of F3H in catechin biosynthesis.  相似文献   
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